Despite popular opinion to the contrary, freezing a snake is not a humane method of euthanasia. The formation of ice crystals in the tissues and on the skin are widely thought to cause intense pain.
Some vets prefer to administer Nembutal/Sodium Pentobarbital, however I have also spoken to specialty exotic vets who claim that it takes a long time to work on snakes…a minimum of 30 minutes..and that they have doubts to the amount of discomfort or stress such a slow acting method may cause the animal.
Additionally, concentrated sodium pentobarbital solutions that are formulated for intravenous use are highly alkaline and may cause irritation to tissue and pain when injected into the animal.
Injection of reptiles with 0.5% to 1% MS222 (Tricaine Methanosulfonate) solution at doses of 250 to 500 mg/kg have been shown to result in a loss of consciousness in most snakes in between 12 and 15 minutes. Respiratory and cardiac functions will remain intact past that time frame therefore a second injection of 50% MS222 solution finishes the animal off. MS222 is highly acidic, which is why it is administered initially in a low concentration buffered dose to induce a loss of consciousness and then is rapidly followed by the 50% dose, which kills the animal in 30 to 60 seconds.
MS222 is administered intracoelemically, which is a fancy way of saying “into the body cavity”.
There are some people who advocate decapitation. This is not a humane way to dispatch a snake. The central nervous system of a snake is capable of withstanding a total depletion of oxygen. This is why decapitation can actually result in a slow death. Some old school vets were known to euthanize by decapitation, then double pith the brain.
Which brings us to pithing. Oft cited and oft performed incorrectly. Like all do-it-yourself veterinary administrations, you better make sure you are well-trained and adept at doing it before you try it. I have seen vets perform it after first rendering an animal unconscious. The procedure consists of inserting a rod into the foramen magnum of the brain and proximal end of the spinal cord.. Here’s the rub. most people who have told me they pith often don’t even know what the foramen magnum is. Enough said.
My vets uses the MS222 route and after watching a couple of my older animals put down this way, it is a route I am comfortable with. After the first injection the animal is gets a little woozy. After about a quarter of an hour the animal loses consciousness. The second injection is given and the animal dies within a minute. I usually hold my snakes during the process.
Another process I have not discussed is the use of Isoflurane. Isoflurane is commonly used as an anesthetic in reptile surgeries.
When my oldest boomslang was euthanized, the vet first anesthetized her in her trap box (which was her hide) with Isoflurane. It took her about 20 minutes to lose consciousness at which she was removed from the trap box and a 50% MS222 injection was given. Again, from my point of view, the process appeared to be completely humane and as distress free as possible as she peaceably went to sleep in her hide.
Bottom line – if you are a responsible and compassionate owner, euthanasia is a defining moment in your relationship with your animal. How you choose to help your snake into death says a lot about the type of person you are. Save a few bucks and do it wrong and you can and probably will give your pet a pretty painful and traumatic end.
Do it right…spend a few bucks and make sure the final moments of your snake’s life are as peaceful as possible.
My Mostly Unnatural World of Reptiles 